This invention is directed to ultraviolet light (UV) curable coating compositions containing an oxalanilide ultraviolet light stabilizer (UV absorber) dissolved therein. The compositions are particularly useful as coatings for a variety of metallized, plastic substrates (both thermoplastic and thermoset), especially as topcoats for providing excellent weathering resistance as evidenced by excellent resistance to humidity and hot/cold cycling.
It is known to apply a thin film of metal to a nonmetallic substrate to make a metallized substrate and to provide the metallized substrate with a protective coating. Such coated, metallized substrates are useful, for example, for such diverse articles as nonmetallic parts on automotive vehicles, and containers and container caps for cosmetics. The plastic substrates for such articles often are composed of heat sensitive materials such as heat sensitive plastics which can distort when exposed to elevated temperatures. It would be desirable to provide coatings for such metallized substrates that can be cured efficiently at temperatures below the temperatures at which such heat sensitive substrates distort. Moreover, it would be desirable to provide coatings for such substrates which are not only decorative, but also are highly adherent to the metallized substrate, and are resistant to weathering as occurs upon prolonged exposure to various atmospheric conditions of temperature and humidity. These and other objects will become apparent to one skilled in the art from the disclosure contained herein.